No offence, but that seems really useless. Your not going to get good data from a smartphone in someones pocket or worse there apartment. You could take a cellphone out wait 15 minutes for a good temperature reading and then send that, but that's way to much effort relative to the value of the data which is basically nonexistent.

Edit: Ahh, pressure sensor. I had no idea most smartphones had anything like that.

No offence taken. Most people think it will be useless. But you are very, very incorrect when you say I'm not going to get good data. I've already got tens of millions of measurements of excellent data. Check out http://pressurenet.cumulonimbus.ca and play around with your local area. Live data goes back about a week, but there's an archive that covers most of 2012. Check out New York City, in late October / early November: Hurricane Sandy.

I'm livestreaming the data to Cliff Mass, a professor of atmospheric science at the University of Washington. He's got a small team analyzing it to calibrate the sensors and as we grow the network, he'll be using the data to improve weather models and try out new systems of forecasting.

That sounds actually really awesome. Congrats on doing something!

Thank you for actually contributing with your actions. I see a lot of rhetoric on climate change but very few people actually willing to do something.